Wind farm expansion will require fridges to be switched off at times of peak …

Professor Roger Kemp of Lancaster University, said: “If there is a sudden
peak in electricity demand the smart freezer would say, ‘OK I’m going to
switch off for half an hour until that peak is over’.”

Consumers could negotiate cheaper energy tariffs for consenting to this and
would not be affected by the temporary switch-off, he said.

“If you didn’t have a smart grid and smart control of domestic equipment, you
would probably find prices would have to go up more because the power system
people would have to build more power stations as back-up.”

The report say that “the ability to manage demand to reflect the output
from wind will be vital to the successful integration of larger amounts of
wind capacity”.

However, it casts doubt on the viability of this solution, warning: “There
is much uncertainty on how effective it will be and at what cost.”

The report finds that the current grid can cope with “up to a 20pc
contribution from wind power without the need for significant upgrades to
the system and using existing balancing mechanisms”.

Beyond that threshold – expected to be crossed by the early 2020s – “managing
the system will become increasingly difficult”, it warns.

The inherently variable nature of wind power will present problems when there
is a mismatch between wind output and consumer demand – either too much wind
or not enough.

“During periods of high demand, wind still often produces very low levels of
output,” the report finds.

“At low levels of penetration [wind energy deployment], this should not be a
major issue and, indeed, up to now security has not been compromised despite
periods of virtually no output from wind and maximum demands. However, as
levels of penetration increase, the situation can be expected to change
adversely.”

If wind power continues to expand beyond 2020, days of negligible wind power
could “present problems for security of supply”.

In the reverse scenario, where wind output is high but demand is low, wind
farm owners could increasingly have to be paid to switch their turbines off
– an “inefficient and costly” solution if it becomes more common.